tracing: Add .percent suffix option to histogram values
Add .percent suffix option to show the histogram values in percentage.
This feature is useful when we need yo undersntand the overall trend
for the histograms of large values.
E.g. this shows the runtime percentage for each tasks.
------
# cd /sys/kernel/debug/tracing/
# echo hist:keys=pid:vals=hitcount,runtime.percent:sort=pid > \
events/sched/sched_stat_runtime/trigger
# sleep 10
# cat events/sched/sched_stat_runtime/hist
# event histogram
#
# trigger info: hist:keys=pid:vals=hitcount,runtime.percent:sort=pid:size=2048 [active]
#
{ pid: 14 } hitcount: 9 runtime: 2.48
{ pid: 16 } hitcount: 38 runtime: 5.11
{ pid: 59 } hitcount: 30 runtime: 10.30
{ pid: 61 } hitcount: 73 runtime: 13.19
{ pid: 64 } hitcount: 1 runtime: 0.22
{ pid: 65 } hitcount: 13 runtime: 2.53
{ pid: 67 } hitcount: 11 runtime: 2.35
{ pid: 69 } hitcount: 8 runtime: 1.40
{ pid: 77 } hitcount: 7 runtime: 1.83
{ pid: 145 } hitcount: 41 runtime: 33.03
{ pid: 152 } hitcount: 8 runtime: 11.90
{ pid: 153 } hitcount: 6 runtime: 8.09
{ pid: 154 } hitcount: 5 runtime: 7.50
Totals:
Hits: 250
Entries: 13
Dropped: 0
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Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Conflicts:
kernel/trace/trace_events_hist.c
2 files changed
